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unicorn/no-magic-array-flat-depth Restriction

What it does

Disallow magic numbers for Array.prototype.flat depth.

Why is this bad?

Magic numbers are hard to understand and maintain. When calling Array.prototype.flat, it is usually called with 1 or Infinity. If you are using a different number, it is better to add a comment explaining the reason for the depth provided.

Examples

Examples of incorrect code for this rule:

array.flat(2);
array.flat(20);

Examples of correct code for this rule:

array.flat(2 /* explanation */);
array.flat(1);
array.flat();
array.flat(Infinity);

How to use

To enable this rule using the config file or in the CLI, you can use:

Config (.oxlintrc.json)

{
  "rules": {
    "unicorn/no-magic-array-flat-depth": "error"
  }
}

Config (oxlint.config.ts)

import { defineConfig } from "oxlint";

export default defineConfig({
  rules: {
    "unicorn/no-magic-array-flat-depth": "error",
  },
});

CLI

oxlint --deny unicorn/no-magic-array-flat-depth

Version

This rule was added in v0.4.2.

References

• Rule Source
• Upstream rule docs
• Open rule in Oxc Playground